1. Field of the Invention
The present invention relates to a synthetic resin insulator comprising a rod or pipe made of reinforced plastic (hereinafter referred to as a reinforced plastic rod) and a holding metal fitting to which the rod is secured, and a method of assembling the insulator.
2. Description of the Prior Art
A reinforced plastic rod produced by impregnating fiber bundles arranged in the axial direction or knitted fiber bundles with a synthetic resin and bonding the impregnated fiber bundles through the resin can resist a very high tensile stress and has a very high ratio of strength to weight. However, it is very difficult to secure such reinforced plastic rod to a holding metal fitting without the formation of cracks in the rod and deterioration thereof; therefore, the rod cannot develop fully satisfactory function as a tension insulator under high tension. In order to obviate this drawback, various structures for holding a reinforced plastic rod by a holding metal fitting have been proposed, and a typical holding structure is disclosed in British Pat. No. 816,926 (U.S. Pat. No. 3,152,392). However, the holding structure disclosed in that patent specification still has such drawbacks that the reinforced plastic rod cannot be secured uniformly to the holding metal fitting, and the rod cracks and is whitened and damaged. The present invention aims to obviate these drawbacks.